1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) International Business Machines Corp., 2006
4 *
5 * Author: Artem Bityutskiy (Битюцкий Артём)
6 */
7
8 /*
9 * This file contains implementation of volume creation, deletion, updating and
10 * resizing.
11 */
12
13 #include <linux/err.h>
14 #include <linux/math64.h>
15 #include <linux/slab.h>
16 #include <linux/export.h>
17 #include "ubi.h"
18
19 static int self_check_volumes(struct ubi_device *ubi);
20
21 static ssize_t vol_attribute_show(struct device *dev,
22 struct device_attribute *attr, char *buf);
23
24 /* Device attributes corresponding to files in '/<sysfs>/class/ubi/ubiX_Y' */
25 static struct device_attribute attr_vol_reserved_ebs =
26 __ATTR(reserved_ebs, S_IRUGO, vol_attribute_show, NULL);
27 static struct device_attribute attr_vol_type =
28 __ATTR(type, S_IRUGO, vol_attribute_show, NULL);
29 static struct device_attribute attr_vol_name =
30 __ATTR(name, S_IRUGO, vol_attribute_show, NULL);
31 static struct device_attribute attr_vol_corrupted =
32 __ATTR(corrupted, S_IRUGO, vol_attribute_show, NULL);
33 static struct device_attribute attr_vol_alignment =
34 __ATTR(alignment, S_IRUGO, vol_attribute_show, NULL);
35 static struct device_attribute attr_vol_usable_eb_size =
36 __ATTR(usable_eb_size, S_IRUGO, vol_attribute_show, NULL);
37 static struct device_attribute attr_vol_data_bytes =
38 __ATTR(data_bytes, S_IRUGO, vol_attribute_show, NULL);
39 static struct device_attribute attr_vol_upd_marker =
40 __ATTR(upd_marker, S_IRUGO, vol_attribute_show, NULL);
41
42 /*
43 * "Show" method for files in '/<sysfs>/class/ubi/ubiX_Y/'.
44 *
45 * Consider a situation:
46 * A. process 1 opens a sysfs file related to volume Y, say
47 * /<sysfs>/class/ubi/ubiX_Y/reserved_ebs;
48 * B. process 2 removes volume Y;
49 * C. process 1 starts reading the /<sysfs>/class/ubi/ubiX_Y/reserved_ebs file;
50 *
51 * In this situation, this function will return %-ENODEV because it will find
52 * out that the volume was removed from the @ubi->volumes array.
53 */
vol_attribute_show(struct device * dev,struct device_attribute * attr,char * buf)54 static ssize_t vol_attribute_show(struct device *dev,
55 struct device_attribute *attr, char *buf)
56 {
57 int ret;
58 struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
59 struct ubi_device *ubi = vol->ubi;
60
61 spin_lock(&ubi->volumes_lock);
62 if (!ubi->volumes[vol->vol_id] || ubi->volumes[vol->vol_id]->is_dead) {
63 spin_unlock(&ubi->volumes_lock);
64 return -ENODEV;
65 }
66 /* Take a reference to prevent volume removal */
67 vol->ref_count += 1;
68 spin_unlock(&ubi->volumes_lock);
69
70 if (attr == &attr_vol_reserved_ebs)
71 ret = sprintf(buf, "%d\n", vol->reserved_pebs);
72 else if (attr == &attr_vol_type) {
73 const char *tp;
74
75 if (vol->vol_type == UBI_DYNAMIC_VOLUME)
76 tp = "dynamic";
77 else
78 tp = "static";
79 ret = sprintf(buf, "%s\n", tp);
80 } else if (attr == &attr_vol_name)
81 ret = sprintf(buf, "%s\n", vol->name);
82 else if (attr == &attr_vol_corrupted)
83 ret = sprintf(buf, "%d\n", vol->corrupted);
84 else if (attr == &attr_vol_alignment)
85 ret = sprintf(buf, "%d\n", vol->alignment);
86 else if (attr == &attr_vol_usable_eb_size)
87 ret = sprintf(buf, "%d\n", vol->usable_leb_size);
88 else if (attr == &attr_vol_data_bytes)
89 ret = sprintf(buf, "%lld\n", vol->used_bytes);
90 else if (attr == &attr_vol_upd_marker)
91 ret = sprintf(buf, "%d\n", vol->upd_marker);
92 else
93 /* This must be a bug */
94 ret = -EINVAL;
95
96 /* We've done the operation, drop volume and UBI device references */
97 spin_lock(&ubi->volumes_lock);
98 vol->ref_count -= 1;
99 ubi_assert(vol->ref_count >= 0);
100 spin_unlock(&ubi->volumes_lock);
101 return ret;
102 }
103
104 static struct attribute *volume_dev_attrs[] = {
105 &attr_vol_reserved_ebs.attr,
106 &attr_vol_type.attr,
107 &attr_vol_name.attr,
108 &attr_vol_corrupted.attr,
109 &attr_vol_alignment.attr,
110 &attr_vol_usable_eb_size.attr,
111 &attr_vol_data_bytes.attr,
112 &attr_vol_upd_marker.attr,
113 NULL
114 };
115 ATTRIBUTE_GROUPS(volume_dev);
116
117 /* Release method for volume devices */
vol_release(struct device * dev)118 static void vol_release(struct device *dev)
119 {
120 struct ubi_volume *vol = container_of(dev, struct ubi_volume, dev);
121
122 ubi_eba_replace_table(vol, NULL);
123 ubi_fastmap_destroy_checkmap(vol);
124 kfree(vol);
125 }
126
find_volume_fwnode(struct ubi_volume * vol)127 static struct fwnode_handle *find_volume_fwnode(struct ubi_volume *vol)
128 {
129 struct fwnode_handle *fw_vols, *fw_vol;
130 const char *volname;
131 u32 volid;
132
133 fw_vols = device_get_named_child_node(vol->dev.parent->parent, "volumes");
134 if (!fw_vols)
135 return NULL;
136
137 fwnode_for_each_child_node(fw_vols, fw_vol) {
138 if (!fwnode_property_read_string(fw_vol, "volname", &volname) &&
139 strncmp(volname, vol->name, vol->name_len))
140 continue;
141
142 if (!fwnode_property_read_u32(fw_vol, "volid", &volid) &&
143 vol->vol_id != volid)
144 continue;
145
146 return fw_vol;
147 }
148
149 return NULL;
150 }
151
152 /**
153 * ubi_create_volume - create volume.
154 * @ubi: UBI device description object
155 * @req: volume creation request
156 *
157 * This function creates volume described by @req. If @req->vol_id id
158 * %UBI_VOL_NUM_AUTO, this function automatically assign ID to the new volume
159 * and saves it in @req->vol_id. Returns zero in case of success and a negative
160 * error code in case of failure. Note, the caller has to have the
161 * @ubi->device_mutex locked.
162 */
ubi_create_volume(struct ubi_device * ubi,struct ubi_mkvol_req * req)163 int ubi_create_volume(struct ubi_device *ubi, struct ubi_mkvol_req *req)
164 {
165 int i, err, vol_id = req->vol_id;
166 struct ubi_volume *vol;
167 struct ubi_vtbl_record vtbl_rec;
168 struct ubi_eba_table *eba_tbl = NULL;
169
170 if (ubi->ro_mode)
171 return -EROFS;
172
173 vol = kzalloc(sizeof(struct ubi_volume), GFP_KERNEL);
174 if (!vol)
175 return -ENOMEM;
176
177 device_initialize(&vol->dev);
178 vol->dev.release = vol_release;
179 vol->dev.parent = &ubi->dev;
180 vol->dev.class = &ubi_class;
181 vol->dev.groups = volume_dev_groups;
182
183 if (req->flags & UBI_VOL_SKIP_CRC_CHECK_FLG)
184 vol->skip_check = 1;
185
186 spin_lock(&ubi->volumes_lock);
187 if (vol_id == UBI_VOL_NUM_AUTO) {
188 /* Find unused volume ID */
189 dbg_gen("search for vacant volume ID");
190 for (i = 0; i < ubi->vtbl_slots; i++)
191 if (!ubi->volumes[i]) {
192 vol_id = i;
193 break;
194 }
195
196 if (vol_id == UBI_VOL_NUM_AUTO) {
197 ubi_err(ubi, "out of volume IDs");
198 err = -ENFILE;
199 goto out_unlock;
200 }
201 req->vol_id = vol_id;
202 }
203
204 dbg_gen("create device %d, volume %d, %llu bytes, type %d, name %s",
205 ubi->ubi_num, vol_id, (unsigned long long)req->bytes,
206 (int)req->vol_type, req->name);
207
208 /* Ensure that this volume does not exist */
209 err = -EEXIST;
210 if (ubi->volumes[vol_id]) {
211 ubi_err(ubi, "volume %d already exists", vol_id);
212 goto out_unlock;
213 }
214
215 /* Ensure that the name is unique */
216 for (i = 0; i < ubi->vtbl_slots; i++)
217 if (ubi->volumes[i] && !ubi->volumes[i]->is_dead &&
218 ubi->volumes[i]->name_len == req->name_len &&
219 !strcmp(ubi->volumes[i]->name, req->name)) {
220 ubi_err(ubi, "volume \"%s\" exists (ID %d)",
221 req->name, i);
222 goto out_unlock;
223 }
224
225 /* Calculate how many eraseblocks are requested */
226 vol->usable_leb_size = ubi->leb_size - ubi->leb_size % req->alignment;
227 vol->reserved_pebs = div_u64(req->bytes + vol->usable_leb_size - 1,
228 vol->usable_leb_size);
229
230 /* Reserve physical eraseblocks */
231 if (vol->reserved_pebs > ubi->avail_pebs) {
232 ubi_err(ubi, "not enough PEBs, only %d available",
233 ubi->avail_pebs);
234 if (ubi->corr_peb_count)
235 ubi_err(ubi, "%d PEBs are corrupted and not used",
236 ubi->corr_peb_count);
237 err = -ENOSPC;
238 goto out_unlock;
239 }
240 ubi->avail_pebs -= vol->reserved_pebs;
241 ubi->rsvd_pebs += vol->reserved_pebs;
242 spin_unlock(&ubi->volumes_lock);
243
244 vol->vol_id = vol_id;
245 vol->alignment = req->alignment;
246 vol->data_pad = ubi->leb_size % vol->alignment;
247 vol->vol_type = req->vol_type;
248 vol->name_len = req->name_len;
249 memcpy(vol->name, req->name, vol->name_len);
250 vol->ubi = ubi;
251 device_set_node(&vol->dev, find_volume_fwnode(vol));
252
253 /*
254 * Finish all pending erases because there may be some LEBs belonging
255 * to the same volume ID.
256 */
257 err = ubi_wl_flush(ubi, vol_id, UBI_ALL);
258 if (err)
259 goto out_acc;
260
261 eba_tbl = ubi_eba_create_table(vol, vol->reserved_pebs);
262 if (IS_ERR(eba_tbl)) {
263 err = PTR_ERR(eba_tbl);
264 goto out_acc;
265 }
266
267 ubi_eba_replace_table(vol, eba_tbl);
268
269 if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
270 vol->used_ebs = vol->reserved_pebs;
271 vol->last_eb_bytes = vol->usable_leb_size;
272 vol->used_bytes =
273 (long long)vol->used_ebs * vol->usable_leb_size;
274 } else {
275 vol->used_ebs = div_u64_rem(vol->used_bytes,
276 vol->usable_leb_size,
277 &vol->last_eb_bytes);
278 if (vol->last_eb_bytes != 0)
279 vol->used_ebs += 1;
280 else
281 vol->last_eb_bytes = vol->usable_leb_size;
282 }
283
284 /* Make volume "available" before it becomes accessible via sysfs */
285 spin_lock(&ubi->volumes_lock);
286 ubi->volumes[vol_id] = vol;
287 ubi->vol_count += 1;
288 spin_unlock(&ubi->volumes_lock);
289
290 /* Register character device for the volume */
291 cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
292 vol->cdev.owner = THIS_MODULE;
293
294 vol->dev.devt = MKDEV(MAJOR(ubi->cdev.dev), vol_id + 1);
295 dev_set_name(&vol->dev, "%s_%d", ubi->ubi_name, vol->vol_id);
296 err = cdev_device_add(&vol->cdev, &vol->dev);
297 if (err) {
298 ubi_err(ubi, "cannot add device");
299 goto out_mapping;
300 }
301
302 /* Fill volume table record */
303 memset(&vtbl_rec, 0, sizeof(struct ubi_vtbl_record));
304 vtbl_rec.reserved_pebs = cpu_to_be32(vol->reserved_pebs);
305 vtbl_rec.alignment = cpu_to_be32(vol->alignment);
306 vtbl_rec.data_pad = cpu_to_be32(vol->data_pad);
307 vtbl_rec.name_len = cpu_to_be16(vol->name_len);
308 if (vol->vol_type == UBI_DYNAMIC_VOLUME)
309 vtbl_rec.vol_type = UBI_VID_DYNAMIC;
310 else
311 vtbl_rec.vol_type = UBI_VID_STATIC;
312
313 if (vol->skip_check)
314 vtbl_rec.flags |= UBI_VTBL_SKIP_CRC_CHECK_FLG;
315
316 memcpy(vtbl_rec.name, vol->name, vol->name_len);
317
318 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
319 if (err)
320 goto out_sysfs;
321
322 ubi_volume_notify(ubi, vol, UBI_VOLUME_ADDED);
323 self_check_volumes(ubi);
324 return err;
325
326 out_sysfs:
327 /*
328 * We have registered our device, we should not free the volume
329 * description object in this function in case of an error - it is
330 * freed by the release function.
331 */
332 cdev_device_del(&vol->cdev, &vol->dev);
333 out_mapping:
334 spin_lock(&ubi->volumes_lock);
335 ubi->volumes[vol_id] = NULL;
336 ubi->vol_count -= 1;
337 spin_unlock(&ubi->volumes_lock);
338 out_acc:
339 spin_lock(&ubi->volumes_lock);
340 ubi->rsvd_pebs -= vol->reserved_pebs;
341 ubi->avail_pebs += vol->reserved_pebs;
342 out_unlock:
343 spin_unlock(&ubi->volumes_lock);
344 put_device(&vol->dev);
345 ubi_err(ubi, "cannot create volume %d, error %d", vol_id, err);
346 return err;
347 }
348
349 /**
350 * ubi_remove_volume - remove volume.
351 * @desc: volume descriptor
352 * @no_vtbl: do not change volume table if not zero
353 *
354 * This function removes volume described by @desc. The volume has to be opened
355 * in "exclusive" mode. Returns zero in case of success and a negative error
356 * code in case of failure. The caller has to have the @ubi->device_mutex
357 * locked.
358 */
ubi_remove_volume(struct ubi_volume_desc * desc,int no_vtbl)359 int ubi_remove_volume(struct ubi_volume_desc *desc, int no_vtbl)
360 {
361 struct ubi_volume *vol = desc->vol;
362 struct ubi_device *ubi = vol->ubi;
363 int i, err, vol_id = vol->vol_id, reserved_pebs = vol->reserved_pebs;
364
365 dbg_gen("remove device %d, volume %d", ubi->ubi_num, vol_id);
366 ubi_assert(desc->mode == UBI_EXCLUSIVE);
367 ubi_assert(vol == ubi->volumes[vol_id]);
368
369 if (ubi->ro_mode)
370 return -EROFS;
371
372 spin_lock(&ubi->volumes_lock);
373 if (vol->ref_count > 1) {
374 /*
375 * The volume is busy, probably someone is reading one of its
376 * sysfs files.
377 */
378 err = -EBUSY;
379 goto out_unlock;
380 }
381
382 /*
383 * Mark volume as dead at this point to prevent that anyone
384 * can take a reference to the volume from now on.
385 * This is necessary as we have to release the spinlock before
386 * calling ubi_volume_notify.
387 */
388 vol->is_dead = true;
389 spin_unlock(&ubi->volumes_lock);
390
391 ubi_volume_notify(ubi, vol, UBI_VOLUME_SHUTDOWN);
392
393 spin_lock(&ubi->volumes_lock);
394 ubi->volumes[vol_id] = NULL;
395 spin_unlock(&ubi->volumes_lock);
396
397 if (!no_vtbl) {
398 err = ubi_change_vtbl_record(ubi, vol_id, NULL);
399 if (err)
400 goto out_err;
401 }
402
403 for (i = 0; i < vol->reserved_pebs; i++) {
404 err = ubi_eba_unmap_leb(ubi, vol, i);
405 if (err)
406 goto out_err;
407 }
408
409 cdev_device_del(&vol->cdev, &vol->dev);
410 put_device(&vol->dev);
411
412 spin_lock(&ubi->volumes_lock);
413 ubi->rsvd_pebs -= reserved_pebs;
414 ubi->avail_pebs += reserved_pebs;
415 ubi_update_reserved(ubi);
416 ubi->vol_count -= 1;
417 spin_unlock(&ubi->volumes_lock);
418
419 ubi_volume_notify(ubi, vol, UBI_VOLUME_REMOVED);
420 if (!no_vtbl)
421 self_check_volumes(ubi);
422
423 return 0;
424
425 out_err:
426 ubi_err(ubi, "cannot remove volume %d, error %d", vol_id, err);
427 spin_lock(&ubi->volumes_lock);
428 ubi->volumes[vol_id] = vol;
429 out_unlock:
430 spin_unlock(&ubi->volumes_lock);
431 return err;
432 }
433
434 /**
435 * ubi_resize_volume - re-size volume.
436 * @desc: volume descriptor
437 * @reserved_pebs: new size in physical eraseblocks
438 *
439 * This function re-sizes the volume and returns zero in case of success, and a
440 * negative error code in case of failure. The caller has to have the
441 * @ubi->device_mutex locked.
442 */
ubi_resize_volume(struct ubi_volume_desc * desc,int reserved_pebs)443 int ubi_resize_volume(struct ubi_volume_desc *desc, int reserved_pebs)
444 {
445 int i, err, pebs;
446 struct ubi_volume *vol = desc->vol;
447 struct ubi_device *ubi = vol->ubi;
448 struct ubi_vtbl_record vtbl_rec;
449 struct ubi_eba_table *new_eba_tbl = NULL;
450 struct ubi_eba_table *old_eba_tbl = NULL;
451 int vol_id = vol->vol_id;
452
453 if (ubi->ro_mode)
454 return -EROFS;
455
456 dbg_gen("re-size device %d, volume %d to from %d to %d PEBs",
457 ubi->ubi_num, vol_id, vol->reserved_pebs, reserved_pebs);
458
459 if (vol->vol_type == UBI_STATIC_VOLUME &&
460 reserved_pebs < vol->used_ebs) {
461 ubi_err(ubi, "too small size %d, %d LEBs contain data",
462 reserved_pebs, vol->used_ebs);
463 return -EINVAL;
464 }
465
466 /* If the size is the same, we have nothing to do */
467 if (reserved_pebs == vol->reserved_pebs)
468 return 0;
469
470 new_eba_tbl = ubi_eba_create_table(vol, reserved_pebs);
471 if (IS_ERR(new_eba_tbl))
472 return PTR_ERR(new_eba_tbl);
473
474 spin_lock(&ubi->volumes_lock);
475 if (vol->ref_count > 1) {
476 spin_unlock(&ubi->volumes_lock);
477 err = -EBUSY;
478 goto out_free;
479 }
480 spin_unlock(&ubi->volumes_lock);
481
482 /* Reserve physical eraseblocks */
483 pebs = reserved_pebs - vol->reserved_pebs;
484 if (pebs > 0) {
485 spin_lock(&ubi->volumes_lock);
486 if (pebs > ubi->avail_pebs) {
487 ubi_err(ubi, "not enough PEBs: requested %d, available %d",
488 pebs, ubi->avail_pebs);
489 if (ubi->corr_peb_count)
490 ubi_err(ubi, "%d PEBs are corrupted and not used",
491 ubi->corr_peb_count);
492 spin_unlock(&ubi->volumes_lock);
493 err = -ENOSPC;
494 goto out_free;
495 }
496
497 ubi->avail_pebs -= pebs;
498 ubi->rsvd_pebs += pebs;
499 ubi_eba_copy_table(vol, new_eba_tbl, vol->reserved_pebs);
500 old_eba_tbl = vol->eba_tbl;
501 vol->eba_tbl = new_eba_tbl;
502 vol->reserved_pebs = reserved_pebs;
503 spin_unlock(&ubi->volumes_lock);
504 }
505
506 if (pebs < 0) {
507 for (i = 0; i < -pebs; i++) {
508 err = ubi_eba_unmap_leb(ubi, vol, reserved_pebs + i);
509 if (err)
510 goto out_free;
511 }
512 spin_lock(&ubi->volumes_lock);
513 ubi->rsvd_pebs += pebs;
514 ubi->avail_pebs -= pebs;
515 ubi_update_reserved(ubi);
516 ubi_eba_copy_table(vol, new_eba_tbl, reserved_pebs);
517 old_eba_tbl = vol->eba_tbl;
518 vol->eba_tbl = new_eba_tbl;
519 vol->reserved_pebs = reserved_pebs;
520 spin_unlock(&ubi->volumes_lock);
521 }
522
523 /*
524 * When we shrink a volume we have to flush all pending (erase) work.
525 * Otherwise it can happen that upon next attach UBI finds a LEB with
526 * lnum > highest_lnum and refuses to attach.
527 */
528 if (pebs < 0) {
529 err = ubi_wl_flush(ubi, vol_id, UBI_ALL);
530 if (err)
531 goto out_acc;
532 }
533
534 /* Change volume table record */
535 vtbl_rec = ubi->vtbl[vol_id];
536 vtbl_rec.reserved_pebs = cpu_to_be32(reserved_pebs);
537 err = ubi_change_vtbl_record(ubi, vol_id, &vtbl_rec);
538 if (err)
539 goto out_acc;
540
541 if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
542 vol->used_ebs = reserved_pebs;
543 vol->last_eb_bytes = vol->usable_leb_size;
544 vol->used_bytes =
545 (long long)vol->used_ebs * vol->usable_leb_size;
546 }
547
548 /* destroy old table */
549 ubi_eba_destroy_table(old_eba_tbl);
550 ubi_volume_notify(ubi, vol, UBI_VOLUME_RESIZED);
551 self_check_volumes(ubi);
552 return err;
553
554 out_acc:
555 spin_lock(&ubi->volumes_lock);
556 vol->reserved_pebs = reserved_pebs - pebs;
557 ubi->rsvd_pebs -= pebs;
558 ubi->avail_pebs += pebs;
559 if (pebs > 0)
560 ubi_eba_copy_table(vol, old_eba_tbl, vol->reserved_pebs);
561 else
562 ubi_eba_copy_table(vol, old_eba_tbl, reserved_pebs);
563 vol->eba_tbl = old_eba_tbl;
564 spin_unlock(&ubi->volumes_lock);
565 out_free:
566 ubi_eba_destroy_table(new_eba_tbl);
567 return err;
568 }
569
570 /**
571 * ubi_rename_volumes - re-name UBI volumes.
572 * @ubi: UBI device description object
573 * @rename_list: list of &struct ubi_rename_entry objects
574 *
575 * This function re-names or removes volumes specified in the re-name list.
576 * Returns zero in case of success and a negative error code in case of
577 * failure.
578 */
ubi_rename_volumes(struct ubi_device * ubi,struct list_head * rename_list)579 int ubi_rename_volumes(struct ubi_device *ubi, struct list_head *rename_list)
580 {
581 int err;
582 struct ubi_rename_entry *re;
583
584 err = ubi_vtbl_rename_volumes(ubi, rename_list);
585 if (err)
586 return err;
587
588 list_for_each_entry(re, rename_list, list) {
589 if (re->remove) {
590 err = ubi_remove_volume(re->desc, 1);
591 if (err)
592 break;
593 } else {
594 struct ubi_volume *vol = re->desc->vol;
595
596 spin_lock(&ubi->volumes_lock);
597 vol->name_len = re->new_name_len;
598 memcpy(vol->name, re->new_name, re->new_name_len + 1);
599 spin_unlock(&ubi->volumes_lock);
600 ubi_volume_notify(ubi, vol, UBI_VOLUME_RENAMED);
601 }
602 }
603
604 if (!err)
605 self_check_volumes(ubi);
606 return err;
607 }
608
609 /**
610 * ubi_add_volume - add volume.
611 * @ubi: UBI device description object
612 * @vol: volume description object
613 *
614 * This function adds an existing volume and initializes all its data
615 * structures. Returns zero in case of success and a negative error code in
616 * case of failure.
617 */
ubi_add_volume(struct ubi_device * ubi,struct ubi_volume * vol)618 int ubi_add_volume(struct ubi_device *ubi, struct ubi_volume *vol)
619 {
620 int err, vol_id = vol->vol_id;
621 dev_t dev;
622
623 dbg_gen("add volume %d", vol_id);
624
625 /* Register character device for the volume */
626 cdev_init(&vol->cdev, &ubi_vol_cdev_operations);
627 vol->cdev.owner = THIS_MODULE;
628 dev = MKDEV(MAJOR(ubi->cdev.dev), vol->vol_id + 1);
629 err = cdev_add(&vol->cdev, dev, 1);
630 if (err) {
631 ubi_err(ubi, "cannot add character device for volume %d, error %d",
632 vol_id, err);
633 vol_release(&vol->dev);
634 return err;
635 }
636
637 vol->dev.release = vol_release;
638 vol->dev.parent = &ubi->dev;
639 vol->dev.devt = dev;
640 vol->dev.class = &ubi_class;
641 vol->dev.groups = volume_dev_groups;
642 dev_set_name(&vol->dev, "%s_%d", ubi->ubi_name, vol->vol_id);
643 device_set_node(&vol->dev, find_volume_fwnode(vol));
644 err = device_register(&vol->dev);
645 if (err) {
646 cdev_del(&vol->cdev);
647 put_device(&vol->dev);
648 return err;
649 }
650
651 self_check_volumes(ubi);
652 return err;
653 }
654
655 /**
656 * ubi_free_volume - free volume.
657 * @ubi: UBI device description object
658 * @vol: volume description object
659 *
660 * This function frees all resources for volume @vol but does not remove it.
661 * Used only when the UBI device is detached.
662 */
ubi_free_volume(struct ubi_device * ubi,struct ubi_volume * vol)663 void ubi_free_volume(struct ubi_device *ubi, struct ubi_volume *vol)
664 {
665 dbg_gen("free volume %d", vol->vol_id);
666
667 ubi->volumes[vol->vol_id] = NULL;
668 cdev_del(&vol->cdev);
669 device_unregister(&vol->dev);
670 }
671
672 /**
673 * self_check_volume - check volume information.
674 * @ubi: UBI device description object
675 * @vol_id: volume ID
676 *
677 * Returns zero if volume is all right and a negative error code if not.
678 */
self_check_volume(struct ubi_device * ubi,int vol_id)679 static int self_check_volume(struct ubi_device *ubi, int vol_id)
680 {
681 int idx = vol_id2idx(ubi, vol_id);
682 int reserved_pebs, alignment, data_pad, vol_type, name_len, upd_marker;
683 const struct ubi_volume *vol;
684 long long n;
685 const char *name;
686
687 spin_lock(&ubi->volumes_lock);
688 reserved_pebs = be32_to_cpu(ubi->vtbl[vol_id].reserved_pebs);
689 vol = ubi->volumes[idx];
690
691 if (!vol) {
692 if (reserved_pebs) {
693 ubi_err(ubi, "no volume info, but volume exists");
694 goto fail;
695 }
696 spin_unlock(&ubi->volumes_lock);
697 return 0;
698 }
699
700 if (vol->reserved_pebs < 0 || vol->alignment < 0 || vol->data_pad < 0 ||
701 vol->name_len < 0) {
702 ubi_err(ubi, "negative values");
703 goto fail;
704 }
705 if (vol->alignment > ubi->leb_size || vol->alignment == 0) {
706 ubi_err(ubi, "bad alignment");
707 goto fail;
708 }
709
710 n = vol->alignment & (ubi->min_io_size - 1);
711 if (vol->alignment != 1 && n) {
712 ubi_err(ubi, "alignment is not multiple of min I/O unit");
713 goto fail;
714 }
715
716 n = ubi->leb_size % vol->alignment;
717 if (vol->data_pad != n) {
718 ubi_err(ubi, "bad data_pad, has to be %lld", n);
719 goto fail;
720 }
721
722 if (vol->vol_type != UBI_DYNAMIC_VOLUME &&
723 vol->vol_type != UBI_STATIC_VOLUME) {
724 ubi_err(ubi, "bad vol_type");
725 goto fail;
726 }
727
728 if (vol->upd_marker && vol->corrupted) {
729 ubi_err(ubi, "update marker and corrupted simultaneously");
730 goto fail;
731 }
732
733 if (vol->reserved_pebs > ubi->good_peb_count) {
734 ubi_err(ubi, "too large reserved_pebs");
735 goto fail;
736 }
737
738 n = ubi->leb_size - vol->data_pad;
739 if (vol->usable_leb_size != ubi->leb_size - vol->data_pad) {
740 ubi_err(ubi, "bad usable_leb_size, has to be %lld", n);
741 goto fail;
742 }
743
744 if (vol->name_len > UBI_VOL_NAME_MAX) {
745 ubi_err(ubi, "too long volume name, max is %d",
746 UBI_VOL_NAME_MAX);
747 goto fail;
748 }
749
750 n = strnlen(vol->name, vol->name_len + 1);
751 if (n != vol->name_len) {
752 ubi_err(ubi, "bad name_len %lld", n);
753 goto fail;
754 }
755
756 n = (long long)vol->used_ebs * vol->usable_leb_size;
757 if (vol->vol_type == UBI_DYNAMIC_VOLUME) {
758 if (vol->corrupted) {
759 ubi_err(ubi, "corrupted dynamic volume");
760 goto fail;
761 }
762 if (vol->used_ebs != vol->reserved_pebs) {
763 ubi_err(ubi, "bad used_ebs");
764 goto fail;
765 }
766 if (vol->last_eb_bytes != vol->usable_leb_size) {
767 ubi_err(ubi, "bad last_eb_bytes");
768 goto fail;
769 }
770 if (vol->used_bytes != n) {
771 ubi_err(ubi, "bad used_bytes");
772 goto fail;
773 }
774
775 if (vol->skip_check) {
776 ubi_err(ubi, "bad skip_check");
777 goto fail;
778 }
779 } else {
780 if (vol->used_ebs < 0 || vol->used_ebs > vol->reserved_pebs) {
781 ubi_err(ubi, "bad used_ebs");
782 goto fail;
783 }
784 if (vol->last_eb_bytes < 0 ||
785 vol->last_eb_bytes > vol->usable_leb_size) {
786 ubi_err(ubi, "bad last_eb_bytes");
787 goto fail;
788 }
789 if (vol->used_bytes < 0 || vol->used_bytes > n ||
790 vol->used_bytes < n - vol->usable_leb_size) {
791 ubi_err(ubi, "bad used_bytes");
792 goto fail;
793 }
794 }
795
796 alignment = be32_to_cpu(ubi->vtbl[vol_id].alignment);
797 data_pad = be32_to_cpu(ubi->vtbl[vol_id].data_pad);
798 name_len = be16_to_cpu(ubi->vtbl[vol_id].name_len);
799 upd_marker = ubi->vtbl[vol_id].upd_marker;
800 name = &ubi->vtbl[vol_id].name[0];
801 if (ubi->vtbl[vol_id].vol_type == UBI_VID_DYNAMIC)
802 vol_type = UBI_DYNAMIC_VOLUME;
803 else
804 vol_type = UBI_STATIC_VOLUME;
805
806 if (alignment != vol->alignment || data_pad != vol->data_pad ||
807 upd_marker != vol->upd_marker || vol_type != vol->vol_type ||
808 name_len != vol->name_len || strncmp(name, vol->name, name_len)) {
809 ubi_err(ubi, "volume info is different");
810 goto fail;
811 }
812
813 spin_unlock(&ubi->volumes_lock);
814 return 0;
815
816 fail:
817 ubi_err(ubi, "self-check failed for volume %d", vol_id);
818 if (vol)
819 ubi_dump_vol_info(vol);
820 ubi_dump_vtbl_record(&ubi->vtbl[vol_id], vol_id);
821 dump_stack();
822 spin_unlock(&ubi->volumes_lock);
823 return -EINVAL;
824 }
825
826 /**
827 * self_check_volumes - check information about all volumes.
828 * @ubi: UBI device description object
829 *
830 * Returns zero if volumes are all right and a negative error code if not.
831 */
self_check_volumes(struct ubi_device * ubi)832 static int self_check_volumes(struct ubi_device *ubi)
833 {
834 int i, err = 0;
835
836 if (!ubi_dbg_chk_gen(ubi))
837 return 0;
838
839 for (i = 0; i < ubi->vtbl_slots; i++) {
840 err = self_check_volume(ubi, i);
841 if (err)
842 break;
843 }
844
845 return err;
846 }
847